Sheet metal bending tool



S p 9 R. E. SMITH 2,255,368

SHEET METAL BENDING TOOL Filed Nov. 18, 1938 2 Sheets-Sheetl INVENTOR ATTORNEYS WITN E55 WITNESS Sept. 9, 1941.

R. E. SMITH SHEET METAL BENDING TOOL Filed Nov. 18 195 2 Sheets-Sheet 2 wriiv m INVENTOR ATTORNEYS Patented Sept. 9, 1941 UNITED STATES PATENT OFFICE SHEET METAL BENDING TOOL Raymond E. Smith, Waukegan, 111. Application November 18, 1938, Serial No. 241,290

7 Claims.

The invention relates to new and improved. tools for bending various articles of sheet metal or the like and is primarily adapted to form folds or flanges on the ends of substantially square or rectangular shaped sheet metal ducts or pipes.

In the installation of heating and air conditioning systems it is essential that the ducts or pipes, usually formed of sheet metal, be joined together end to end in a manner to effect a perfect fitting. In the joining of the pipes in such systems it is customary to form a turned down flange on two sides thereof and to employ a key slidable over the flanges for locking the same.

The primary object of the present invention resides in the provision of a device which will support one end of the duct or pipe and embodying means for turning back and folding down a flange without distorting the major body portion of the duct or pipe whereby the ends of two flanged pipes can be suitably joined and united.

Another object of the invention is to provide a frame having a multiplicity of various sized fingers adapted to be inserted within the end of the pipe for holding it in position while forming flanges thereon by a specially designed tool pivotally carried on said frame; the various sized fingers permitting automatic adjustment of the device to fit any width of duct or pipe within the limits of the device.

A still further object of the invention resides in the provision of an edge folding and crimping device embodying means for attaching the tool to a work bench or the like whereby freedom of operation is accomplished, the duct or pipe supporting frame being swingably mounted on the bench and the folding tool being likewise swingably mounted on the journal supporting the duct or pipe carrying frame.

The invention will be fully and comprehensively understood from a consideration of the following detailed description when read in connection with the accompanying drawings which form a part of the application.

In the drawings:

Figure 1 is a side elevational view of the assemloled tool with the several parts thereof in the initial operating position;

Figure 2 is a top plan view of the tool with parts broken away for clarity;

Figure 3 is a perspective view of a section of a removable portion of the flange forming tool;

Figure 4 is a perspective view in section illustrating the portion of the device to which the member illustrated in Figure3 is attached;

Cir

Figure 5 is a perspective view in section of the duct or pipe supporting frame and illustrating the relation of the variable fingers;

Figures 6, '7, 8, 9 and 10 are substantially vertical sectional views illustrating the position of the tool with respect to the duct or pipe during the several steps of operation for forming a flange thereon;

Figure 11 is a fragmentary perspective view of two pipes joined in the conventional manner after the forming of the flanges on theends thereof using the device according to the present invention;

Figure 12 is an end elevational view of the tool in position on a work bench; and

Figure 13 is a perspective view of the cradle employed for supporting the tool on a work bench.

Referring to the drawings for a more detailed description thereof wherein there is illustrated the preferred embodiment of the invention, the flange forming device indicated generally by the reference numeral l5 comprises a pair of frames 16 and H, the frame I! overlying the frame l6 and both frames being supported on axles l8 as illustrated in Figure 2 of the drawings. The frames l6 and H are pivotally connected by means of the integrally formed ears I9 and 20 formed on each end of the frames and having aligned openings 2| through which the axles l8 project. In other words, a hinge joint is formed by means of the ears l9 and 20 and the axles ill.

The frame l6, as illustrated in Figure 5 of the drawings, is substantially triangular shaped in cross-section and includes a plurality of fingers 22 carried by the arms 23, integral with, welded or'otherwise secured to the frame. The arms 23 and fingers 22 are formed in spaced relation on the frame l6 and are of varied widths in order to accommodate various sized ducts or pipes. It isto be understood that when using the device two or more fingers will be disposed within the pipe and in abutting relation with the interior surface thereof and provide the required support when forming the folded edges thereon which will be hereinafter described.

The frame I! carrying the flange forming means is clearly illustrated in Figures 3 and 4 of the drawings and is held spaced from the lower frame It and pivotally connected thereto as above described. It will be noted that a portion of the frame I! is substantially triangular shaped in cross-section, the top area 24 thereof being formed with a plurality of fingers 25 which are of the same diameter as the finger 22 of the frame It and which are arranged in spaced relation in the same manner as the fingers 22. The fingers 25 are shorter in length, however, than the fingers 22, and in cooperation with the plate 25, provide the flange forming means. The plate 26 is attached to the top surface 2d of the frame i? by means of screw fasteners or the like 21, and as shown in Figure 3 of the drawings, said plate is formed with a tapered tongue 28 which extends therefrom and overlies the fingers 25. Due to the tapered shape of the tongue 23, a space will be formed between said tongue and the fingers 25 which will be sufficient to admit the end of the duct or pipe being flanged. The

' frame H has a portion 29 extending beyond the triangular formation which adds rigidity to the frame and at the same time renders the size of the frame ll substantially equal to the frame It and the relation of the two frames is clearly illustrated in the various views of the drawings.

It will be noted that the fingers 22 and 25, respectively, are formed with rounded edges which facilitates the placement of the duct or pipe thereon, it being understood that the pipe end will be disposed in the space provided by the formation of the fingers 22.

Actuating handles 3t and 3t are bolted or otherwise secured to the frames 56 and H, re-

spectively, and are employed to swing said frames about the axles l8 when using the device. The position of the handles when the device is attached to a work bench 32 is illustrated in Figure 12 of the drawings, the handle 3i being employed to raise the frame If during the formation of a flange on the end of the pipe and the handle 3% being employed to disengage the frame It from the pipe after formation of the flange as will be hereinafter described.

For attaching the pair of frames to a work bench or the like, there is provided the cradle indicated generally at 33 and best illustrated in Figures 12 and 13 of the drawings, said cradle being substantially U-shaped and formed with upwardly extending leg members 34, the ends of said leg members being cupped at 35 forming the supporting means for the axles it. The cupshaped portions 35 are formed with extending lips 32 on which the extensions 63 of the plate 26 rest when the frame I? is raised to the position shown in Figures '7 and 10 of the drawings. If desired, removable pins 44 may be employed to secure the axles within the cupped portions 35. The cradle 33 is fastened to the work bench 32 by screws or the like 35' and the intermediate portion of said cradle has pivotally connected thereto an arcuate-shaped catch 35 which engages the handle 36 for rigidly holding the lower frame H5 in position. The catch 35 swings about its pivot 3? to permit the frame IE to swing upwardly to the position shown in Figure 8 of the drawings for disengaging the pipe therefrom.

The operation and use of the tool is believed to be readily apparent from the above description taken in connection with the illustrated drawings. When desiring to form interlocking flanges on the ends of ducts or pipes it is first necessary to slit the four corners of the pipe as indicated at 33 in Figure '7 of the drawings. The end of the duct or pipe is then positioned over appropriate sized fingers 22 and will be supported thereon as shown in Figure 6 of the drawings. When positioning the duct or pipe the end thereof will rest between the fingers 25 and tongue 28 of the upper frame H, and the initial posiaesases tioning of the pipe prior to formation of the flange is shown in Figure 6 of the drawings. The second step shown in Figure 7 of the drawings consists in swinging the frame ll about its axle through the medium of the handle 3| whereupon the flange 33 of the pipe or duct 48 will be partially formed. With the frame ll resting in the position illustrated in Figure 7 of the drawings, the frame it? is then disengaged and moved to the position shown in Figure 8 of the drawings, said disengagement being accomplished by releasing the catch 35 to permit the frame to swing about its axis through the medium of the handle 30 whereupon the fingers 25 and the flange 28 are slipped away from the flange 39. The two frames are then moved back to the initial posi tion as shown in Figure 9 of the drawings and by swinging the frame 3'! upwardly as shown in Figure 10 of the drawings the flange 33 can be bent downwardly without disturbing the rounded edge of said flange. The bending down of the flange is accomplished through the medium of the corner of the plate 25 and the tapered edge of the tongue 23. Both frames are then removed in the manner above described and the pipe or duct iii re-positioned for forming a flange on the opposite side thereof, the operation being repeated.

It will be readily apparent that there is provided a flange forming tool that will effectively hold the duct or pipe in position while permitting the formation of a perfect flange. Figure 11 of the drawings illustrates a pair of ducts or pipes 49 having the flanges 32% formed thereon and joined through the use of a key ll. It will be noted that the unobstructed ends of the pipes are arrangedin overlapped relation whereby a perfect fitting is provided. Flanges formed with the tool of the present invention permit of facile application of the key 11 since said flanges are of perfect formation thereby permitting ready application of the key. L

Also it will be understood, of course by those skilled in the art that variations in the hereinabove described device involving the substitution of substantial equivalents for the devices described are intended to be comprehended within the spirit of the present invention and that the invention is capable of extended applicat on and s not confined to the exact showing of th drawings nor to the precise construction de scribed and, therefore, such changes and modiflcations may be made therein as do not affect the spirit of the invention nor exceed th scop thereof as expressed in the a pended c aims v What is claimed is: h J

l. A flange forming tool for sheet metal pipes comprising, a first frame, a plurality of fin ers extendmg from and integral with said frame said fingers being of different widths and ar ranged in spaced relation on said frame and adapted to engage the pipe during the flange forming operation, a second frame disposed above said first frame and pivotally attached thereto, said second frame swingable in an arc relative to said first frame, a plurality of fingers extending from said second frame and arranged in spaced relation in back of and substantially parallel to said first-mentioned fin ers WhSll Said frames are in a particular angular relationship, said second frame and fingers receiving the end portion of the pipe to be bent rearwardly when said frames are in the aforesaid relationship, and a member carried by said second frame having a tapered portion overlying the fingers carried thereby and in spaced relation thereto.

2. A flange forming tool for sheet metal pipes, comprising, a first frame, a plurality of fingers formed on arms extending from said frame, said first frame and fingers adapted to engage the pipe during the flange forming operation, a second frame disposed above said first frame and pivotally attached thereto, said second frame swingable in an are relative to said first frame, a plurality of fingers extending from said second frame and lying behind and substantially parallel to said first-mentioned fingers when said frames are in a particular angular relationship, and a member attached to said second frame having a tapered portion overlying the fingers carried thereby and in spaced relation thereto, said second frame and fingers receiving the end portion of the pipe to be bent rearwardly when said frames are in the aforesaid relationship.

3. A flange forming tool for sheet metal pipes, comprising a first frame, a plurality of fingers formed on arms extending from said frame, said first frame and fingers adapted to engage the pipe during the flange forming operation, a second frame disposed above said first frame and pivotally attached thereto, said second frame sWingab-le in an are relative to said first frame, a plurality of fingers extending from said second frame and lying behind and substantially parallel to said first-mentioned fingers when said frames are in a particular angular relationship, a member attached to said second frame having a tapered portion overlying the fingers carried thereby and in spaced relation thereto, said second frame and fingers receiving the end portion of the pipe to be bent rearwardly when said frames are in the aforesaid relationship, and means on each of said frames for independently actuating said frames.

4. A flange forming tool for sheet metal pipes, comprising, a first frame, a plurality of fingers extending from and integral with said frame, said first frame and fingers adapted to engage the pipe during the flange forming operation, a

relationship, and means for swingably supporting said frames.

5. A flange forming tool for sheet metal pipes,

comprising, a first frame, a plurality of fingers formed on arms extending from said frame, said first frame and fingers adapted to engage the pipe during the flange forming operation, a second frame disposed above said first frame and pivotally attached thereto, said second frame of the pipe to be bent rearwardly when said frames are in the aforesaid relationship, and means for swingably supporting said frames.

6. A flange forming tool for sheet metal pipes, comprising, a first frame, a plurality of fingers formed on arms extending from said frame, said first frame and fingers adapted to engage the pipe during the flange forming operation, a second frame disposed above said first frame and having a plurality of fingers lying behind and substantially parallel to said first-mentioned fingers when said frames are in a particular angular relationship, said frames being hingedly connected by ears integrally formed on the ends thereof with said second frame swingable in an are relative to said first frame, means for maintaining said ears in position comprising axles projecting therefrom, and means for attaching said frames to a base, said means including a substantially U-shaped cradle having upwardly extending arms for receiving the projecting ends of said axles.

7. A flange forming tool for sheet metal pipes, comprising, an elongated substantially triangular-shaped frame, the base portion of said triangular-shaped frame being perpendicularly disposed and having arms extending at an angle therefrom, finger-like portions formed on said arms and lying in a substantially horizontal plane, a second elongated frame pivotally attached to said first frame, said second frame swingable in an are relative to said first frame, said second frame being substantially triangular-shaped in cross section with the base portion thereof disposed in a horizontal plane and at right angles to the base of said first frame when said frames are in a particular angular relationship, finger-like portions carried by said second frame and lying behind and substantially parallel to said first-mentioned fingers, said second frame and fingers receiving the end portion of the pipe to be bent rearwardly when said frames are in the aforesaid relationship, and means for swingably supporting said frames.

RAYMOND E. SMITH. 

